Which drug class is explicitly cited as increasing the risk of orthostatic hypotension due to alpha-1 blockade?

Which drug class is explicitly cited as increasing the risk of orthostatic hypotension due to alpha-1 blockade?

• A. Nonselective peripheral alpha-1 blockers
• B. Beta-blockers
• C. ACE inhibitors
• D. Statins

Answer: (A)

Blocking alpha-1 receptors in the vascular smooth muscle prevents the normal vasoconstrictive response that keeps blood pressure up when you stand. When these receptors are blocked broadly throughout the peripheral vessels, standing causes more blood pooling in the legs and less reflex vasoconstriction, leading to a drop in blood pressure—orthostatic hypotension. Nonselective peripheral alpha-1 blockers do this across many vascular beds, so they carry a higher risk of orthostatic hypotension. Other drug classes listed don’t produce orthostatic hypotension primarily through alpha-1 blockade: beta-blockers affect heart rate and contractility rather than vascular constriction via alpha-1 receptors; ACE inhibitors lower BP through RAAS effects; statins don’t influence vascular tone in this way. If a drug is more selective for prostate alpha-1 receptors, the orthostatic risk is typically lower because the vascular alpha-1 blockade is less complete.

Blocking alpha-1 receptors in the vascular smooth muscle prevents the normal vasoconstrictive response that keeps blood pressure up when you stand. When these receptors are blocked broadly throughout the peripheral vessels, standing causes more blood pooling in the legs and less reflex vasoconstriction, leading to a drop in blood pressure—orthostatic hypotension.

Nonselective peripheral alpha-1 blockers do this across many vascular beds, so they carry a higher risk of orthostatic hypotension. Other drug classes listed don’t produce orthostatic hypotension primarily through alpha-1 blockade: beta-blockers affect heart rate and contractility rather than vascular constriction via alpha-1 receptors; ACE inhibitors lower BP through RAAS effects; statins don’t influence vascular tone in this way. If a drug is more selective for prostate alpha-1 receptors, the orthostatic risk is typically lower because the vascular alpha-1 blockade is less complete.